
Yesterday I saw in New York Times a series of 15 very professional pictures of Ahmedinijad´s visit to Iran´s uranium enrichment facilities. I wondered if the pics were authentic and what caused Ahmedinijad to show Iran's most secret site to the world. Anyway, if those thousands of silvery centrifuges are functional, Iran may be in fact more advanced in this area than the USA. The pic below show ultra rapid centrifuges 1.5 meter high, while the American centrifuges shown above are ten and more meter high. America had 3 gas enrichment facilities but closed 2 and let the third to decay. Then they decided to change to more efficient gaseous diffusion technology, which uses semi membranes. But Iran´s dwarf centrifuges made of carbon fiber polymers may resuscitate the technology.

A typical gas centrifuge works like this: Uranium hexafluoride gas is spun in a rotating column. The heavier U-238 is flung closest to the wall. The lighter U-235 isotope is scooped out. Centrifuges are connected in series and parallel to form cascades, producing the desired capacities and enrichment levels. Technically, the thing is very difficult, because the centrifuge has to spin very rapidly as capacity increases square of the speed. The major limitation is the material the rotor is made of as it has to stand those forces plus stand up to the uranium hexafluoride, which is very corrosive.
The technology became easier with the advances in carbon fibers, which allows to produce better separation components. Computers can now ran complicated gas flow models with relative ease. These models reduced the level of intelligence needed to understand and manage the fluid dynamics. And there are a whole new world of materials, electric engines, etc. which make the business of making enriched uranium much more easy and reliable.
Enriched uranium is unexpensive and many countries would happily sell their surplus but only for energy generation. Iran has no need to develope an independent enrichment industry for pacific purposes. The fact that it is doing it, publicly and against the world´s will, can only mean that (1) they have the illusion of becoming a great nuclear power, as behooves to the Great Persian Nation, in spite of their camel herding economy. That would give them great pride and satisfaction. For a while. (2) They want to have nuclear bomb manufacturing capability for military purposes. They may feel menaced by their neighbors, having been attacked by Saddam Hussein not so long ago. It was not a small war, certainly not for Iran that lost one million soldiers. Then and there they decided that they needed rockets and big bombs.
PS: Having slept on the problem, I have decided that Ahmedinijad is behaving in the typical Third World leader pattern, that is, he has one big shiny anti-American triumphal project to sooth his burning sense of inferiority. Peron nationalized British owned railways, Nasser nationalized the Suez canal, Kim exploded an atom bomb, etc. This does not solve Israel's problem, as the next step after having the bomb, is the urge to demonstrate its power.
PSS: Having slept more on the problem, now I am less sure that it is a prestige project, and not a self-defense deeply felt imperative. I shall stop sleeping on things because it only causes more confusion.















































